This essentially reverts commit 71fc47a9adf8ee89e5c96a47222915c5485ac437
("ACPI: basic initramfs DSDT override support"), because the code simply
isn't ready.

It did ugly things to the init sequence to populate the rootfs image
early, but that just ended up showing other problems with the whole
approach. The fact is, the VFS layer simply isn't initialized this
early, and the relevant ACPI code should either run much later, or this
shouldn't be done at all.

For 2.6.25, we'll just pick the latter option. We can revisit this
concept later if necessary.

Cc: Dave Hansen
Cc: Tilman Schmidt
Cc: Andrew Morton
Cc: Thomas Renninger
Cc: Eric Piel
Cc: Len Brown
Cc: Christoph Hellwig
Cc: Markus Gaugusch
Signed-off-by: Linus Torvalds